Humans use rocks for a wide variety of purposes, including construction and as a source of valuable minerals located inside the rocks. Additionally, humans use rocks for decoration, recreation and thermal purposes. Humans are not the only organisms that utilize rocks, as plants, animals and fungi use rocks for stability, digestive purposes and as a substrate.
Rocks have been used in the construction of primitive dwellings and structures for nearly as long as humans have walked the Earth. As humans evolved, they began modifying the rocks into tools, such as knives, spear points and arrowheads. Later, humans learned how to remove important ores, including iron, silver and gold, from rocks.
Granite is a very commonly used rock in construction. In addition to being abundant, its properties make it well suited for a variety of applications. Decomposed or crushed granite is often used for decorative purposes in gardens or to improve dirt roads. Very fine grades of granite are used to add texture to paints and floor coverings.
Plant roots often grow around rocks, which gives them added stability. Many animals, including crocodiles and some birds, ingest rocks regularly. The animals do not eat the rocks for nutrition; instead, the rocks work to help grind up tough food items.